Data from: Systematics and taxonomy of the Snubnose Darter, Etheostoma simoterum (Cope)

A taxonomic revision of Etheostoma simoterum (Cope) published in 2007
resulted in the recognition of six species, with two species distributed
in the Tennessee River system. A newly defined Etheostoma simoterum was
restricted to populations in the Holston River above the confluence of the
North and South Forks, and the Russell Fork system of the Ohio River
drainage. A newly described species, Etheostoma tennesseense Powers
& Mayden, included all other populations historically considered
Etheostoma simoterum in the Tennessee River system from near the mouth of
the Duck River upstream to the Clinch River, including the Holston River
below the forks. A subsequent study utilizing molecular phylogenetics and
analysis of male nuptial coloration did not support the recognition of
Etheostoma tennesseense. Molecular phylogenies resolve both Etheostoma
simoterum and Etheostoma tennesseense as paraphyletic. In addition, it was
determined that male coloration patterns are not diagnostic for the more
restricted and new definition of Etheostoma simoterum. In this study, we
examine the systematics of Etheostoma simoterum using meristic traits
sampled from more than 1,000 specimens, including Cope's syntype
series of Hyostoma simoterum and Powers and Mayden's paratopotype
series of Etheostoma tennesseense. Our results show a pattern of clinal
variation, where meristic traits are higher in the in the lower Tennessee
River system. Comparisons of populations above and below the forks of the
Holston River show no differences in meristic traits, but populations
sampled from the Watauga River system exhibit scale counts lower than any
other population of Etheostoma simoterum. We cannot reject the hypothesis
that Etheostoma tennesseense is conspecific with the specimens that
comprise the Hyostoma simoterum syntype series. Based on both
morphological and molecular species delimitation strategies, we treat
Etheostoma tennesseense as a synonym of Etheostoma simoterum.